Israel's response to the Iranian challenge has been out of synch with developing realities for some time. Recently though, it has become dangerously counter-productive, anchored as it is in denial. As Israel intensifies its role as threatener-in-chief, and clings to a "more sticks, bigger sticks" line, events all around are moving on.

The supposed logic behind Israel's escalating threats, suggesting it is ready to go it alone militarily, is threefold. It pressures Iran, thereby increasing international leverage in negotiations; a nervous world feels compelled to up sanctions and deliver results; and the path is smoothed to international acceptance of possible future Israeli action. Except that the logic (always a tenuous one) is now being repudiated on all three fronts.

Iran apparently views the threats as a reason to pursue more vigorously, not desist from, its enrichment program. In general, Iran's perception that it is the threatened party (surrounded by U.S. forces in Iraq, Afghanistan and the Arabian Gulf) adds impetus to its weapons-acquisition program. Israeli threats only add to that momentum. Sanctions tend to be a plodding, blunt and ineffective policy instrument. Iranian technological advances have outpaced sanctions every time. Anyway, the prospects of intensifying collective UN sanctions has likely been buried in the rubble of America's spat with Russia over Georgia and its breakaway provinces.

But the collapse of Israel's policy has been most dramatic in eliciting a public and vocal pushback against Israeli military action - from, of all places, the United States. All of America's top military brass have gone on record recently cautioning against a military strike against Iran - and each time after having held meetings with senior Israeli officials. It seems clear that as far as the Pentagon is concerned, there will be no third front in its broader Middle East quagmire and no military green light to Israel.

In addition to losing its efficacy, the "threatener-in-chief" position is also based on a false and now more transparently false premise - namely, that Israel has a military option that carries an acceptable level of risk. American reticence is just one consideration. Several influential studies, most recently one from the Institute for Science and International Security, in Washington, suggest that an attack would only strengthen Tehran's resolve to acquire a bomb, and that its centrifuge program could be quickly rebuilt. An attack would very likely rally the public around the most hard-line elements of the Iranian regime. Already the saber-rattling has allowed President Mahmoud Ahmadinejad's faction to distract attention from its economic mismanagement and to play the nationalism card.

These concerns are well-known, but it's worth recapping them: The region would be radically, and perhaps in the medium term irreversibly, destabilized, with a potentially huge blowback for both Israel and the U.S. Israel is understandably keen to avoid a confrontation on several fronts with Iran and its allies - but an attack would create the optimal conditions for exactly that eventuality to be realized. Iranian enmity for generations would be guaranteed and friendly regional regimes shaken, or worse. For American and coalition troops in Iraq, Afghanistan and even the Gulf, an already harsh reality would likely become untenable, and that's even before one considers the effects on oil markets and implications for world food prices and instability, and for European dependence on Russian energy supplies. Israel quite simply cannot and should not risk it.

The good news is - there are better options. For one, Israel should be leading, or at least contributing to, rather than retarding, a policy re-think on Iran. Instead, when the U.S. sends Under-Secretary of State William Burns to sit in on talks with Iran in Geneva or considers opening an interest section in Tehran, Israel takes umbrage. The same is true when our back-channel mediators with Syria, the Turks, host Iran's leaders.

Israel needs to encourage this direct hard-headed diplomatic engagement between its friends and Iran - contributing talking points of its own and suggesting the dialogue address a broad range of issues of concern to Israel. Israel might even wrong-foot its adversaries and advance a constructive regional dynamic by developing an offer occasionally hinted at by President Shimon Peres - that Israel will support a Middle East free of weapons of mass destruction in the context of regional peace, mutual recognition and security guarantees.

Beyond that, Israel should de-emphasize its unilateral military options and stress confidence in its own deterrence capacity vis-a-vis Iran. Rather than irresponsibly scaring its own public and broadcasting fear to the region, Israel's message can be that it is uniquely placed to meet the military challenges potentially posed by Iran. In fact, without giving anything new away, Israel might reiterate that of all regional actors, it has reason to be the least concerned by developments on the Iranian side. Mutual deterrence would be an acceptable, if undesirable, outcome. That would create the sense of this being a shared problem far more than the desperate cries of gewalt and threats of unilateral action.

Don't expect preventive diplomacy to be swift or simple - but Israel would be making a terrible, even fatal, mistake if it attacked Iran. It does no one, least of all itself, any favors with the parrot-like repetition of the "threatener-in-chief" mantra.

Daniel Levy, a senior fellow at the New America and Century Foundations, was a former adviser in the Israeli Prime Minister's Office, and was the lead Israeli drafter of the Geneva Initiative.

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